Netapp SIS operations: compression and/or deduplication

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The sis command manages SIS operations: compression and/or deduplication. Data compression can be used on-the-fly, and/or as a scheduled background operation. This can be followed by deduplication, which is a method of reducing disk space usage by eliminating duplicate data blocks on a FlexVol volume, where only a single instance of each unique data blocks is stored.

Why you need to RUN: 

Deduplicated Volumes or Aggregates Vulnerable to bug 657692

To prevent data avaiability disruption or severe performance impact please address the issue
If your FlexVol volume or the aggregate containing the FlexVol volume is 70% full or more it is
recommended to run the
sis start -s /vol/
command for systems that are on 7-Mode or
volume efficiency start -vserver -volume
-scan-old-data true
command for systems that are running clustered Data ONTAP.
This will delete the existing fingerprint database and build a new one on the volumes and
aggregates.This can be a long running operation, however it will not require additional space
and will resolve any pre-existing issues with stale fingerprints. Deleting the deduplication
metadata does not affect the savings already on disk or the access to the logical data.

The path parameter is the full path of a FlexVol volume, its format is /vol/vol_name.
First Check to make sure the licenses are installed
NAS> license
nearstore_option xxxxxZH
a_sis xxxxxCG
Enable sis (deduplication) on the volume
NAS> sis on /vol/testVol
SIS for “/vol/testVol” is enabled.
Already existing data could be processed by running “sis start -s /vol/testVol”.
Initiate deduplication service
NAS> sis start -s /vol/testVol
Sis status will display the state and running status on all volumes
NAS> sis status
Path       State     Status   Progress
/vol/Shares        Enabled                Idle        Idle for 10:05:52
/vol/testVol       Enabled                Idle        Idle for 08:48:40
/vol/luns              Disabled               Idle        Idle for 2330:43:02
/vol/vm                Enabled                Idle        Idle for 00:09:35
View the status on a specific volume
NAS> sis status /vol/testVol
Path       State     Status   Progress
/vol/testVol       Enabled                Idle        Idle for 00:11:23
After sis completes, use df to show the amount saved and deduplication percentage
NAS> df -sh /vol/testVol
Filesystem          used      saved    %saved
/vol/testVol/     519GB   754GB   59%
Verify that sis is scheduled to run frequent enough at the times you want
NAS> sis config
Path       Schedule
/vol/shares         sun-sat@0
/vol/testVol       sun-sat@0
/vol/luns              sun-sat@0
/vol/vm                sun-sat@0
Below is the help output of sis config
NAS> sis help config
sis config [ [ -s schedule ]
– Sets up, modifies, and retrieves the schedule of SIS volumes.
Reschedule for nightly at 11pm
NAS> sis config -s sun-sat@23 /vol/testVol
Verify the new configuration
NAS> sis config /vol/testVol
Path       Schedule
/vol/testVol       sun-sat@23

sis status Examples:

This command displays the status of all SIS enabled volumes. The following example shows the status output in short format:
  toaster> sis status
Path State Status Progress
/vol/dvol_1 Enabled Idle Idle for 04:53:29
/vol/dvol_2 Enabled Pending Idle for 15:23:41
/vol/dvol_3 Disabled Idle Idle for 37:12:34
/vol/dvol_4 Enabled Active 25 GB Scanned
/vol/dvol_5 Enabled Active 25 MB Searched
/vol/dvol_6 Enabled Active 40 MB (20%) Done
/vol/dvol_7 Enabled Active 30 MB Verified
/vol/dvol_8 Enabled Active 10% Merged
/vol/dvol_9 Enabled Active 23 MB Scanned, 20 MB Compressed

The dvol_1 is Idle. The last SIS operation on the volume was finished 04:53:29 ago.

The dvol_2 is Pending for resource limitation. The SIS operation on the volume will become Active when the resource is available.
The dvol_3 is Idle because the SIS operation is disabled on the volume.
The dvol_4 is Active. The SIS operation is doing whole volume scanning. So far, it has scanned 25GB of data.
The dvol_5 is Active. The operation is searching for SIS data, there are 25MB of data already searched.
The dvol_6 is also Active. The operation has saved 40MB of data. This is 20% of the total SIS data found in the searching stage.
The dvol_7 is Active. It is verifying the metadata of processed data blocks. This process will remove unused metadata.
The dvol_8 is Active. Verified metadata is being merged. This process will merge together all verified metadata of processed data blocks to an internal format which supports fast SIS operation.
The dvol_9 is Active. The operation is scanning the volume and so far it has compressed 20MB of data.

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